How to Diagnose a Hyundai Elantra not Starting?

Model: Hyundai Elantra

Year Model: 2009

Mileage: 37012km

Fuel : Gasoline

Displacement : 1600cc

T/A : All

1) Condition:

1. Engine Not Cranking
2. GDS(Global Diagnostic System) Cannot communicate to ECU(Engine Control Unit.
3. Engine Cranking But Not Starting

2) Cause:

1. Due to weak Battery
2. Due to inside passenger fuse box.
3. ECU

3) Diagnosis

1. Recharge Battery
2. Check Data link connector power and Ground at same time check for CAN communication = Failed.
3. Visual inspection = ECU sealed broken due to other workshop attemp to open and repair.
4. Replace ECU But still not communicating.
5. Replace inside passenger fuse box.
6. Reprogram immobilizer key = Communication now OK .

4) Repair Guides

1. Recharge Battery.
2. Replace Inside passenger fuse box.
3. Replace ECU.

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